It seems to me that the only advantage of heap over binary tree is to find the smallest item in the heap in complexity of O(1) instead of O(log(2)n) in binary tree.
Worst case complexity in case of binary tree will be O(n) when binary tree converges to an array while in heap it remains O(log(n)). you can use balanced binary trees like red black or AVl but then it wud become more complex and would require more memory.